Based on what Neptune users have reported thus far, you WILL need special bootup procedures for this PSU. See KnC's troubleshooting guide under the heading "PSU powers off when ASIC boards are connected".

If you haven't bought your PSU yet, get EVGA 1300W Supernova G2, good reports so far. Or Seasonic X-1250.
Or, 3 x Cooler Master V850.